Question

Why is dU (change in internal energy)= heat absorbed (Q[v])at constant Temperature and Volume.? And why is dH (enthalpy change)= heat change (Q[p]) at constant temperature and pressure? I do understand why constant pressure and volume is specified but why should the temperature be constant in both cases? shouldn't the first case imply dU=0 at constant temperature?

Answer 1

\[\Delta U=Q+W \]
\[W=0\]

Answer 2

W = -PΔV

Answer 3

I think we assume constant temperature so that we can calculate the total energy change without losing internal energy due to heat lost or gained.

Answer 4

Ok guys what is your educational qualification . Tell me so I can give answer as u can understand. Ok have a nice day

Answer 5

PLEASE HELP!!
Complete the analogy below.
amplitude : loudness :: frequency : _________
A.

Answer 6

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A. opaque
B. polarized
C.

Answer 7

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creating navigati

Answer 8

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invented SCUBA
lived in Sealab II
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Answer 9

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Answer 10

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Answer 11

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Answer 12

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Answer 13

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Answer 14

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Answer 15

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Answer 16

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Answer 17

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Answer 18

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33=8^5z+4

Answer 19

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Answer 20

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A.

Answer 21

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A. 0.08 g/L
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Answer 22

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Answer 23

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https://learning.k12.com/content/enforced/437405-COF_ID125380/Picture2.

Answer 24

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https://learning.k12.com/content/enforced/437405-COF_ID125380/Picture1.